Relationship between biomarkers and findings on low-dose computed tomography in hospitalised patients with acute exacerbation of COPD.

Background: Acute exacerbations of COPD (AECOPD) and community acquired pneumonia (CAP) often coexist. Although chest radiographs may differentiate between these diagnoses, chest radiography is known to underestimate the incidence of CAP in AECOPD. In this exploratory study, we prospectively investigated the incidence of infiltrative changes using low-dose computed tomography (LDCT). Additionally, we investigated whether clinical biomarkers of CAP differed between patients with and without infiltrative changes. Methods: Patients with AECOPD in which pneumonia was excluded using chest radiography underwent additional LDCT-thorax. The images were read independently by two radiologists; a third radiologist was consulted as adjudicator. C-reactive protein (CRP), procalcitonin (PCT), and serum amyloid A (SAA) at admission were assessed. Results: Out of the 100 patients included, 24 had one or more radiographic abnormalities suggestive of pneumonia. The interobserver agreement between two readers (Cohen's κ) was 0.562 (95% CI 0.371-0.752; p<0.001). Biomarkers were elevated in the group with radiological abnormalities compared to the group without abnormalities. Median (interquartile range (IQR)) CRP was 76 (21.5-148.0) mg·L-1 compared to 20.5 (8.8-81.5) mg·L -1 (p=0.018); median (IQR) PCT was 0.09 (0.06-0.15) µg·L-1 compared to 0.06 (0.04-0.08) µg·L-1 (p=0.007); median (IQR) SAA was 95 (7-160) µg·mL-1 compared to 16 (3-89) µg·mL-1 (p=0.019). Sensitivity and specificity for all three biomarkers were moderate for detecting radiographic abnormalities by LDCT in this population. The area under the receiver operating characteristic curve was 0.66 (95% CI 0.52-0.80) for CRP, 0.66 (95% CI 0.53-0.80) for PCT and 0.69 (95% CI 0.57-0.81) for SAA. Conclusion: LDCT can detect additional radiological abnormalities that may indicate acute-phase lung involvement in patients with AECOPD without infiltrate(s) on the chest radiograph. Despite CRP, PCT and SAA being significantly higher in the group with radiological abnormalities on LDCT, they proved unable to reliably detect or exclude CAP. Further research is warranted.

Whole-body-MR imaging including DWIBS in the work-up of patients with head and neck squamous cell carcinoma: a feasibility study.

OBJECTIVES: To assess the feasibility of whole-body magnetic resonance imaging (WB-MRI) including diffusion-weighted whole-body imaging with background-body-signal-suppression (DWIBS) for the evaluation of distant malignancies in head and neck squamous cell carcinoma (HNSCC); and to compare WB-MRI findings with (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG-PET/CT) and chest-CT. METHODS: Thirty-three patients with high risk for metastatic spread (26 males; range 48-79 years, mean age 63 ± 7.9 years (mean ± standard deviation) years) were prospectively included with a follow-up of six months. WB-MRI protocol included short-TI inversion recovery and T1-weighted sequences in the coronal plane and half-fourier acquisition single-shot turbo spin-echo T2 and contrast-enhanced-T1-weighted sequences in the axial plane. Axial DWIBS was reformatted in the coronal plane. Interobserver variability was assessed using weighted kappa and the proportion specific agreement (PA). RESULTS: Two second primary tumors and one metastasis were detected on WB-MRI. WB-MRI yielded seven clinically indeterminate lesions which did not progress at follow-up. The metastasis and one second primary tumor were found when combining (18)F-FDG-PET/CT and chest-CT findings. Interobserver variability for WB-MRI was κ=0.91 with PA ranging from 0.82 to 1.00. For (18)F-FDG-PET/CT κ could not be calculated due to a constant variable in the table and PA ranged from 0.40 to 0.99. CONCLUSIONS: Our WB-MRI protocol with DWIBS is feasible in the work-up of HNSCC patients for detection and characterization of distant pathology. WB-MRI can be complementary to (18)F-FDG-PET/CT, especially in the detection of non (18)F-FDG avid second primary tumors.

MR imaging of the posterior hypophysis in children with tuberculous meningitis.

The syndrome of inappropriate antidiuretic hormone secretion (SIADH) contributes to the morbidity and mortality in children with tuberculous meningitis (TBM). MRI assists in the early diagnosis of TBM and absence of the normal posterior pituitary bright spot (PPS) on T1-weighted MRI in TBM may indicate the functional integrity of the posterior hypophysis. The objective of this retrospective descriptive study of 22 children with TBM was to determine the prevalence of an absent PPS on T1-weighted MRI in children with TBM and its correlation with serum sodium levels (hyponatremia), severity of disease at presentation, and developmental outcome after 6 months. The prevalence of absent PPS in children with TBM was 55%. No significant correlation was found between the PPS and serum sodium status (p = 0.41) or severity of disease at presentation (p = 0.104). There was however a correlation between absent PPS and poorer developmental outcome at 6-month follow-up (p = 0.027).